Skip to content

Iterate

Summary

  • Internal name: Iterate
  • Category: Control Flow
  • Purpose: Run a nested sub-workflow once per integer in a range, exposing the current value in a loop variable.
  • Task type: Connector - see Tasks Overview > Connector Tasks for what this means before reading further.

Compatibility

  • Minimum AndroMate version: 1.1.0

  • Maximum AndroMate version: 1.1.0

  • Minimum Android: Android 13 (API 33)

  • Maximum Android tested: Android 16 (API 36)

  • Supported manufacturers:

    • Samsung (One UI 6.x / 7.x / 8.x)
    • Other manufacturers - not supported yet (Xiaomi HyperOS and Google Pixel are being adapted)

  • Required permissions:

    • None (permissions depend entirely on whatever tasks are placed inside "do")

Detailed description

The Iterate task is AndroMate's native for loop. It runs the sub-workflow embedded under its "do" key once for every integer from start_index to end_index inclusive, writing the current value into iteration_variable_input before each pass.

In the outer graph, Iterate behaves exactly like a normal task - one incoming link, one outgoing "to" link, followed once every pass of the loop has completed. All the repetition happens inside the task, not in the graph's Links.

The sub-workflow under "do" shares the same variable dictionary as the rest of the workflow: it can read any variable declared in the outer Start, and any output it produces (e.g. from a task inside the loop body) is visible to tasks that come after Iterate in the outer graph too.

Input parameters

Parameter Type Required Possible values Android Compatibility AndroMate Compatibility Default
iteration_variable_input String Yes A declared variable name starting with $ Android 13 (API 33) -> Android 16 (API 36) 1.1.0 -> 1.1.0 ""
start_index Integer No Any integer Android 13 (API 33) -> Android 16 (API 36) 1.1.0 -> 1.1.0 0
end_index Integer No Any integer ≥ start_index to actually loop Android 13 (API 33) -> Android 16 (API 36) 1.1.0 -> 1.1.0 0
do Object (sub-workflow) Yes A nested workflow object - see The do sub-workflow below Android 13 (API 33) -> Android 16 (API 36) 1.1.0 -> 1.1.0 -

Output parameters

The Iterate task itself produces no outputs. Any variable written by a task inside "do" updates the shared workflow context normally, as if that task ran directly in the outer graph.

Exceptions

Code Exception Name Description
CONNECTOR-TASK-ERROR-001 No Sub Tasks The "do" field is missing or empty - a connector task must contain a sub-workflow to run.

Note: start_index > end_index is not an error - the loop simply runs zero times.

Execution flowchart

flowchart TD
    Start([Iterate]) --> CheckDo{do sub-workflow\npresent?}
    CheckDo -->|No| E1[CONNECTOR-TASK-ERROR-001\nNO_SUB_TASKS]
    CheckDo -->|Yes| Loop[i = start_index]
    Loop --> CheckRange{i <= end_index?}
    CheckRange -->|No| Continue[Follow outer 'to' link]
    CheckRange -->|Yes| SetVar[Set iteration_variable_input = i]
    SetVar --> RunSub[Run do sub-workflow]
    RunSub --> Increment[i = i + 1]
    Increment --> CheckRange

    Continue --> Success([VoidResult])
    E1 --> Error([Exception])

    style Start fill:#e3f2fd
    style Success fill:#c8e6c9
    style Error fill:#ffcdd2
    style RunSub fill:#fff9c4
    style SetVar fill:#c8e6c9

How it works:

  1. Check do: raises CONNECTOR-TASK-ERROR-001 if the sub-workflow is missing or empty.
  2. Loop: for i from start_index to end_index inclusive:
  3. writes i into iteration_variable_input,
  4. runs the "do" sub-workflow to completion (from its StartSubTask to its End).
  5. Continue: once every pass has run (or immediately, if start_index > end_index), the engine follows the outer "to" link.

The do sub-workflow

do is a nested workflow object, structured like a normal workflow body but using StartSubTask instead of Start as its entry point:

"do": {
  "StartSubTask": [{ "id": "10001" }],
  "TextReport": [
    { "id": "10002", "texte": "Iteration number: $i", "texte_type": 0 }
  ],
  "End": [{ "id": "10003" }],
  "Links": [
    { "from": "10001", "to": "10002" },
    { "from": "10002", "to": "10003" }
  ]
}
  • StartSubTask only takes an "id" - no variables, Time_out, or exec_policy (those belong solely to the outer workflow's real Start).
  • Any task type may be used inside, including another Iterate or ForEachElement for nested loops.
  • All ids are increasing integers, never a string prefix. Number the outer workflow starting at 1000; number every "do" (at any depth) starting at 10001, incrementing across every "do" in the same workflow rather than resetting - see Workflow Concepts > Nested Sub-Workflows for the full rule.
  • The sub-workflow's own Links/End are scoped to itself - they don't interact with the outer graph's Links.

Input parameter details

1. Input parameter: iteration_variable_input

The name of a declared variable that receives the current loop index (as a string) before each pass.

Example

"iteration_variable_input": "$i"

Details

  • Must start with $ and must already be declared in the outer Start.variables.
  • Read as a literal variable name - no resolution applied to this field itself (same convention as SetAndromateVariable's variable_input).

2. Input parameter: start_index / end_index

The inclusive integer range to loop over.

Example

"start_index": 1,
"end_index": 10

Details

  • Both optional - default to 0.
  • If start_index > end_index, the loop body never runs (not an error).

Complete JSON example

Prints "Iteration number: 1" through "Iteration number: 5", using variable $i:

{
  "Start": [
    { "id": "1000", "variables": [{ "variableName": "$i", "variableValue": "0", "is_kpi": false }] }
  ],
  "Iterate": [
    {
      "id": "1001",
      "title": "Print 1 to 5",
      "iteration_variable_input": "$i",
      "start_index": 1,
      "end_index": 5,
      "do": {
        "StartSubTask": [{ "id": "10001" }],
        "TextReport": [
          { "id": "10002", "texte": "Iteration number: $i", "texte_type": 0 }
        ],
        "End": [{ "id": "10003" }],
        "Links": [
          { "from": "10001", "to": "10002" },
          { "from": "10002", "to": "10003" }
        ]
      }
    }
  ],
  "End": [{ "id": "1002" }],
  "Links": [
    { "from": "1000", "to": "1001" },
    { "from": "1001", "to": "1002" }
  ]
}